Gray Moon Sponge

Spheciospongia confoederata

The gray moon sponge, belonging to the family Clionaidae, is a massive and smooth sponge with a distinctive gray color and a leathery texture. It features numerous crater-like oscula on its outer ridge, which are openings that facilitate water flow through the sponge. This species can grow to a substantial size, reaching up to 100 cm in length and 30 cm in thickness. Divers can encounter this sponge in subtropical regions, specifically from Central California to central Baja California, at depths ranging from 0 to 26 meters. The gray moon sponge is sessile, meaning it remains attached to a substrate and does not move. It is a member of the class Demospongiae, which are known to be hermaphroditic. The life cycle begins with the zygote developing into a free-swimming parenchymella larva, which eventually settles on a suitable substrate to grow into a young sponge. Divers encountering the gray moon sponge will find it firmly anchored to rocky surfaces, adding to the underwater landscape with its unique texture and form. Its conservation status has not been evaluated by the IUCN, and there are no noted threats to humans. Observing this sponge provides insight into the diverse and complex ecosystems of subtropical marine environments.